This invention relates to inductors. In particular, this invention relates to high frequency inductors, particularly those suitable for use as surface mount components.
Inductors are of course well known in the electronic art and it is will known that any length of conducting material will have some inductance associated with it. In many radio devices, particularly radios operating in the high frequency ranges, above 800MHz for example, useful small inductance value inductors are fabricated by short circuiting small lengths of transmission line at one end. (The open-circuit end of the transmission line has an inductance associated with it.) Some of these short circuited transmission line inductors are fabricated by plating strips of conductive material onto dielectric materials. The plated materials form a transmission line center conductor and an outer conductor with the center and outer conductors shorted together.
Many high-frequency inductors use a polymeric material having low dielecric constants and high dielectric losses. (Some of the prior art polymeric materials have dielectric constants between two and four in the frequency range between 800 and 900 MHz and have a dielectric loss approaching 0.0013.) While this material has certain desirable electrical characteristics, it is difficult to re-design inductors using this material because of its own fabrication requirements.
A ceramic material or glass material that has low dielectric loss and low dielectric constant that are more easily fabricated might be an improvement over the prior art. Because these other materials are relatively easy to work with, they may be formed into shapes and sizes that permit space savings in compact radio circuits.